"This paper provides information about developing a Windows Store device app to customize the capture experience and provide additional features for a specific camera. The intended audience is independent hardware vendors (IHVs) and original equipment manufacturers (OEMs) who are interested in providing a Windows Store device app to differentiate their attached or embedded camera. Some sections of this paper assume that the reader is familiar with JavaScript, C++, and Media Foundation. This paper contains an appendix with special requirements for internally embedded cameras. "

"Windows 8 apps easily access all the sensors on a Windows 8 machine. But Windows 8 apps can’t access any sensors on a Windows 8 machine without first asking the user’s permission.

Asking Permission

Windows 8 apps are safe. That’s fundamental. Where desktop apps could (and can) do whatever the developer wants, Windows 8 apps are limited only to what the user allows. Developers ask for device access by the application manifest. This XML file is in every Windows 8 app. It is manipulated by the GUI editor or notepad (for the die hard). The manifest is how applications tell the operating system what sensors it intends to use. Just the manifest is not enough. Once requested, the operating system will verify access with the user first.

Important note: checking webcam lets you capture photos. However, to capture video (including access to the vide stream) you need to ask for webcam and microphone. That’s just how it works.

Capture a Photo

Privacy is a huge concern to most customers. Part of the Windows Store app certification process includes checking for the presence of a privacy policy if your app declares any capabilities which could affect privacy.

MSDN has a section (4.1.1) explaining what is expected from the privacy policy. I won't quote it here, but some important points jump out (emphasis mine):